Nondestructive testing of raw materials and weldments

English nameNon-destructive testing(abbreviationNDT)，NDT（Non-destructive testing）It is the general name of all technical means to use the characteristics of sound, light, magnetism and electricity to detect whether there are defects or non-uniformity in the tested object, give the information such as the size, location, nature and quantity of defects, and then determine the technical state of the tested object (such as qualified or not, remaining life, etc.) without damaging or affecting the service performance of the tested object.

Nondestructive testing is a test method to check the surface and internal quality of the inspected parts without damaging the working state of the workpiece or raw materials.

Common flaw detection methods include:XOptical ray flaw detection, ultrasonic flaw detection, magnetic particle flaw detection, eddy current flaw detectionγRadiographic inspection, penetrant inspection(Physical flaw detection methods such as fluorescent flaw detection and dye detection).

Compared with destructive testing, nondestructive testing has the following characteristics.firstIt is non-destructive, because it will not damage the service performance of the detected object during detection; second, it has fullsquareBecause the detection is non-destructive, the whole detection of the detected object can be carried out when necessarysquareSurface detection, which is impossible for destructive detection; third, it has the whole process. Destructive detection is generally only applicable to the detection of raw materials, such as tension, compression, bending, etc. commonly used in mechanical engineering. Destructive inspection is carried out for manufacturing raw materials. For finished products and articles in process, destructive inspection cannot be carried out unless they are not prepared to continue to serve Nondestructive testing does not damage the service performance of the tested object. Therefore, it can not only test the whole process of manufacturing raw materials, intermediate process links and final products, but also test the equipment in service.

through the use ofNDT, it can find the defects in the interior and surface of materials or workpieces, measure the geometric characteristics and dimensions of workpieces, and measure the internal composition, structure, physical properties and state of materials or workpieces.NDTIt can be applied to product design, material selection, processing and manufacturing, finished product inspection, in-service inspection (maintenance), etc., and can play an optimization role between quality control and cost reduction.

NDTIt is also conducive to the safe operation and / or effective use of the product. Through the detection of internal defects of the product, the product is improved from the following aspects:1Improve the manufacturing process;2Reduce manufacturing cost;3Improve the reliability of products;4Safe operation of equipment.

NDT scope:

Inspection of weld surface defects. Check the welding quality of weld surface cracks, incomplete penetration and weld leakage.2Inspection of inner cavity: check surface cracks, peeling, pull wires, scratches, pits, bulges, spots, corrosion and other defects.3. status check. When some products(Such as worm gear pump, engine, etc)After work, perform endoscopic inspection according to the items specified in the technical requirements.4Assembly inspection. When required and required, use Yatai Optoelectronic Industrial video endoscope to check the assembly quality;After assembly or a process is completed, check whether the assembly position of all parts and components meets the requirements of drawings or technical conditions；Whether there are assembly defects.5. inspection of surplus materials. Check the residual internal debris, foreign materials and other surplus materials in the inner cavity of the product.